The most basic form of a bookmark comprises a single elongate laminar element, cut from a sheet, which can easily be inserted in and removed from a book. Such a bookmark is popular because it is cheap to make, can be made decorative and easy to use. However, the reader has to remove the bookmark when reading and to re-insert the bookmark to mark his most recently read page, and, if he closes the book before moving the bookmark in this manner he loses the most recently read page. Thus successful use of such a bookmark requires some co-ordination and organization by the user.
Many different types of more complex bookmarks have been developed, and these generally comprise a number of working parts which have to be made separately and fitted together during manufacture; a useful review thereof is provided in U.S. Pat. No. 4,941,684. A problem with these, and the bookmark forming the subject of this United States patent, is that they are complicated to manufacture and use, expensive to manufacture and are bulky and not particularly easy to carry around when not in use.
There are many bookmarks which include some form of clip which is used to retain a page or set of pages—the clip must be removed and then clipped back to a different position when the marker is to be moved. An example is U.S. Pat. No. 6,015,166, which describes various forms of clips. The pages cannot be turned normally whilst the clip is attached to the page currently being read.
There are also automated bookmarks, which do not need to be moved by the user when the bookmark is used. The bookmarks include a page retaining element which has a movement which allows a page to be turned normally, with the page retaining element lifting up and then being rotated away from the current page, thereby to release the page retaining element and then reposition it on the next page. An example is shown in U.S. Pat. No. 4,793,632; this is a complex mechanical design which is expensive to manufacture and bulky.
In some cases, the bookmark is designed to allow pages to be slipped out from under a clip. An example of this is U.S. Pat. No. 4,932,351. This patent includes two different embodiments. In one embodiment the bookmark includes a metal wire acting as a page retainer clip attached to a metal book cover clip, and this is currently produced for sale as a product called the “Pagekeeper”. In another described embodiment, the bookmark may be formed from a one-piece molded plastic element. A problem with this prior art is that the page must be turned by a user in a given way—it must be turned in such a way as to allow the page to be slipped out from underneath the page retainer clip. Any other kind of turning is likely to damage the page being turned. Also, where the bookmark is formed of molded plastic rather than of metal, the design does not have a workable operation—in particular, the page retainer clip lacks robustness. Furthermore, when the book cover clip is made in the same plastic molding as the page retainer clip, if the plastics material is sufficiently flexible to allow the page retainer clip to be moved to a page being read, the book cover clip lacks grip whilst if the plastics material is sufficiently rigid to provide the book cover clip with grip, the page retainer clip is insufficiently flexible to be moved to a page being read.
Another automated bookmark is shown in European patent EP0816121, also known as a product called the “Automark”. This bookmark is cut out from a single laminar element, and is therefore relatively inexpensive to manufacture. However, the bookmark suffers from a number of disadvantages:
a) it lacks robustness since the arm which attaches the page retaining element to the remainder of the bookmark is deliberately narrowed to enhance the flipping motion of the page retaining element.
b) it is somewhat difficult to position in a book; the positioning is not intuitive, which makes it difficult for normal users to use properly.
c) it does not work particularly well with thick sets of pages, as the page retaining element tends to slip out from the current page.
PCT/GB2005/003325 describes an automated bookmark, which is formed as a laminar element. An arrangement of such a bookmark is shown in FIGS. 1a and 1b and FIGS. 2a and 2b of this specification. The bookmark 1 is suitable for use in a book having a spine 3 and a plurality of rectangular pages 5a, 5b, 5c, 5d, each page having a top 7, a bottom 9, a free side edge 11, and an attached side edge 13 attached at the spine of the book 3. FIGS. 1a and 1b show an embodiment of the bookmark 1 in use, engaging with different pages of the book (holding more pages in FIG. 1b than are held in FIG. 1a).
Referring to FIGS. 2a and 2b, the known bookmark comprises an anchor 18, an arm 17 and page retaining element 19 attached thereto, the anchor 18 having locating means for positioning the bookmark with respect to the book in a preferred configuration which is determined by the construction of the locating means. The locating means is provided by a side 15 of the bookmark, which is arranged to face the spine 3 of the book or of a page therein so as to locate the bookmark, by a holding force provided by the spine 3 of the book, with respect to the book in the preferred configuration.
The page retaining element 19 comprises a page retaining edge 19a that is arranged to engage the top 7 (or bottom 9) of a page, thereby retaining the page in the back of the book when the book is opened. When the side 15 of the bookmark abuts the spine 3 of the book, at least a portion of the page retaining edge 19a is arranged to make at an angle with the top of the retained page. The angle is such that when the retained page is turned, in order to reveal a next page in the book, the retained page is released and the page retaining edge engages with the next page. Referring specifically to FIG. 2b, this type of bookmark does not work particularly well with thick sets of pages, as the page retaining element tends to slip out from the current page.
Thus in summary there are problems which the applicant has identified with respect to the prior art automated bookmarks which are formed as a laminar element. One is that when it is placed in a closed book the pages either side of the page retaining element tend to splay from each other due to the angling of the arm and the page retaining element, and this effect becomes greater the greater the number of pages being held is. Furthermore, the bookmarks only work with a relatively small number of pages gripped therein and a bookmark may need to be moved to different positions in the book several times during reading, since once the page retaining element is disposed on a page relatively remotely from the anchor the page retaining element tends to twist away from the page. The page retaining element tends to slide off the marked page, which is an effect which is desired during releasing of the page being turned but which is detrimental when the bookmark is in its normal page marking state. In essence, the prior art automated bookmarks were either elaborate mechanical devices or did not tend to work well with thick sets of pages, or indeed whole books which are relatively thick.
It would be desirable to provide an automated bookmark that is more effective than prior art automated bookmarks. It would also be desirable to provide an automated bookmark which is relatively simple and inexpensive to manufacture and particularly convenient to use.